javascript - 跨浏览器 JavaScript(不是 jQuery...)滚动到顶部动画

Question

我正在寻找一个可以应用于链接的简单、跨浏览器的“滚动到顶部”动画。我不想要 jQuery/Moo 等 JS 库。

// jQuery Equivilant to convert to pure JS...
$('html, body').animate({scrollTop:0}, 400);

对于在进入图书馆之前应该 100% 学习 JS 的人来说，我是一个完美的案例。 :(

Answer 1

function scrollTo(element, to, duration) {
    if (duration <= 0) return;
    var difference = to - element.scrollTop;
    var perTick = difference / duration * 10;

    setTimeout(function() {
        element.scrollTop = element.scrollTop + perTick;
        if (element.scrollTop === to) return;
        scrollTo(element, to, duration - 10);
    }, 10);
}

演示:

function runScroll() {
  scrollTo(document.body, 0, 600);
}
var scrollme;
scrollme = document.querySelector("#scrollme");
scrollme.addEventListener("click",runScroll,false)

function scrollTo(element, to, duration) {
  if (duration <= 0) return;
  var difference = to - element.scrollTop;
  var perTick = difference / duration * 10;

  setTimeout(function() {
    element.scrollTop = element.scrollTop + perTick;
    if (element.scrollTop == to) return;
    scrollTo(element, to, duration - 10);
  }, 10);
}

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</p>
<button id=scrollme type="button">To the top</button>